continued beefing up the backend

This commit is contained in:
Goren Barak 2023-11-17 11:06:46 -05:00
parent ffb76dd38e
commit 2f20415224
5 changed files with 23 additions and 114 deletions

View file

@ -1,102 +0,0 @@
use crate::parse::ast::*;
pub fn fasm_codegen(expr: Expr) -> String {
let mut asm_text = String::new();
let mut asm_data = String::new();
asm_text.push_str("format ELF64 executable 3\n");
asm_text.push_str("segment readable executable\n");
asm_text.push_str("entry _start\n");
asm_text.push_str("_start:\n");
asm_data.push_str("segment readable writeable\n");
match expr {
Expr::MathExpr(e) => {
asm_text.push_str(format!("\tmov r10, {:?}\n", e.left).as_str());
asm_text.push_str(format!("\tmov r11, {:?}\n", e.right).as_str());
match e.operator {
// If the operator is addition.
MathOperator::OP_ADD => {
asm_text.push_str("\tadd r10, r11\n");
asm_text.push_str("\tmov rax, r10\n");
},
// If the operator is multiplication.
MathOperator::OP_MULT => {
asm_text.push_str("\timul r10, r11\n");
asm_text.push_str("\tmov rax, r10\n");
},
// If the operator is division.
MathOperator::OP_DIV => {
asm_text.push_str("\tmov rax, r10\n");
asm_text.push_str("\tmov rdx, r11\n");
asm_text.push_str("\tidiv r10, r11\n");
asm_text.push_str("\tmov rax, r10\n");
},
// If the operators is subtraction.
MathOperator::OP_SUB => {
asm_text.push_str("\tsub r10, r11\n");
asm_text.push_str("\tmov rax, r10\n");
},
// If the operator is modulo.
MathOperator::OP_MOD => {
asm_text.push_str("\tmov rax, r10\n");
asm_text.push_str("\tmov rdx, r11\n");
asm_text.push_str("\tidiv r10, r11\n");
asm_text.push_str("\tmov rax, rdx\n");
}
}
},
Expr::FunCall(e) => {
for (i, p) in e.params.iter().enumerate() {
match i {
0 => {
// First parameter. Put in %rdi.
asm_text.push_str(format!("\tmov rdi, {:?}\n", p.value).as_str());
},
1 => {
// Second parameter. Put in %rsi.
asm_text.push_str(format!("\tmov rsi, {:?}\n", p.value).as_str());
},
2 => {
// Third parameter. Put in %rdx.
asm_text.push_str(format!("\tmov rdx, {:?}\n", p.value).as_str());
},
3 => {
// Fourth parameter. Put in %rcx.
asm_text.push_str(format!("\tmov rcx, {:?}\n", p.value).as_str());
},
4 => {
// Fifth parameter. Put in %r8.
asm_text.push_str(format!("\tmov r8, {:?}\n", p.value).as_str());
},
5 => {
// Sixth parameter. Put in %r9.
asm_text.push_str(format!("\tmov r9, {:?}\n", p.value).as_str());
},
_ => {
// Parameters after the sixth parameter are pushed to the stack.
asm_text.push_str(format!("\tpush {:?}\n", p.value).as_str());
}
}
}
asm_text.push_str(format!("call {:?}", e.name).as_str());
},
Expr::VarDefenition(e) => {
asm_data.push_str(format!("{} dq {:?}", e.name, e.value).as_str());
},
_ => unimplemented!("sorry unimplemented"),
}
let asm = format!("{}{}", asm_text, asm_data);
println!("{}", asm);
asm
}

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@ -1 +0,0 @@
goren@goren.13806:1700158488

View file

@ -27,9 +27,9 @@ pub fn fasm_codegen(expr: Expr) -> String {
// If the operator is division.
MathOperator::OP_DIV => {
asm_text.push_str("\tmov rax, r10\n");
asm_text.push_str("\tmov rdx, r11\n");
asm_text.push_str("\tidiv r10, r11\n");
asm_text.push_str("\tmov rax, r10\n");
asm_text.push_str("\txor rdx, rdx\n");
asm_text.push_str("\tidiv r11\n");
// The quotient is now stored in %rax.
},
// If the operators is subtraction.
MathOperator::OP_SUB => {
@ -39,10 +39,10 @@ pub fn fasm_codegen(expr: Expr) -> String {
// If the operator is modulo.
MathOperator::OP_MOD => {
asm_text.push_str("\tmov rax, r10\n");
asm_text.push_str("\tmov rdx, r11\n");
asm_text.push_str("\tidiv r10, r11\n");
asm_text.push_str("\txor rdx, rdx\n");
asm_text.push_str("\tidiv r11\n");
asm_text.push_str("\tmov rax, rdx\n");
// The remainder will now be stored in the %rax register.
}
}
},
@ -91,11 +91,18 @@ pub fn fasm_codegen(expr: Expr) -> String {
},
Expr::VarDefenition(e) => {
asm_data.push_str(format!("{} dq {:?}", e.name, e.value).as_str());
asm_data.push_str(format!("\t{} dq {:?}", e.name, e.value).as_str());
},
Expr::VarReference(e) => {
asm_text.push_str(e.name);
},
_ => unimplemented!("sorry unimplemented"),
}
asm_text.push_str("\tmov rax, 60 ; 60 is the system call number for exit.\n");
asm_text.push_str("\txor rdi, rdi ; 0 is the exit code we want.\n");
asm_text.push_str("\tsyscall ; this is the instruction to actually perform the system call.");
let asm = format!("{}{}", asm_text, asm_data);
println!("{}", asm);
asm

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@ -5,8 +5,5 @@ use crate::parse::ast::*;
pub mod parse;
fn main() {
fasm_codegen(Expr::VarDefenition(VarDefenition {
name: "hi",
value: 100,
}));
fasm_codegen(Expr::MathExpr(Math { left: 30, right: 4, operator: MathOperator::OP_DIV}));
}

View file

@ -4,6 +4,7 @@ pub enum Expr<'a> {
FunCall(FunCall<'a>),
FunDefenition(FunDefenition<'a>),
VarDefenition(VarDefenition<'a>),
VarReference(VarReference<'a>),
}
// MATH EXPRESSION
@ -51,8 +52,15 @@ pub struct FunParamCall {
pub value: u64,
}
// VARIABLES
#[derive(Debug)]
pub struct VarDefenition<'a> {
pub name: &'a str,
pub value: u64,
}
#[derive(Debug)]
pub struct VarReference<'a> {
pub name: &'a str,
}